[Fix] ngx cubejs.watch() not producing errors

[PieterVanZyl-Dev]

[Fix] ngx cubejs.watch() not producing errors.
[Spelling] apiInstace -> apiInstance

Check List

• [N/A] Tests has been run in packages where changes made if available
• [N/A] Linter has been run for changed code
• [N/A] Tests for the changes have been added if not covered yet
• [N/A] Docs have been added / updated if required

Issue Reference this PR resolves

#3961

Description of Changes Made (if issue reference is not provided)

Added a try catch to throw errors when the watch() promise fails.

[PieterVanZyl-Dev]

@vasilev-alex

I think this is in your area of expertise.

[codecov]

Codecov Report

Merging #3974 (ad068a3) into master (3afe2b1) will increase coverage by 0.23%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3974      +/-   ##
==========================================
+ Coverage   57.79%   58.02%   +0.23%     
==========================================
  Files         126      127       +1     
  Lines       10524    10646     +122     
  Branches     2556     2592      +36     
==========================================
+ Hits         6082     6177      +95     
- Misses       3967     3993      +26     
- Partials      475      476       +1     

Flag	Coverage Δ
cube-backend	58.02% <ø> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...schema-compiler/src/compiler/DataSchemaCompiler.js	52.24% <0.00%> (-0.94%)	⬇️
packages/cubejs-backend-shared/src/env.ts	33.52% <0.00%> (-0.83%)	⬇️
packages/cubejs-api-gateway/src/graphql.ts	4.16% <0.00%> (-0.62%)	⬇️
...ejs-schema-compiler/src/parser/GenericSqlParser.ts	56.93% <0.00%> (-0.45%)	⬇️
...cubejs-query-orchestrator/src/driver/BaseDriver.js	26.06% <0.00%> (-0.32%)	⬇️
...es/cubejs-schema-compiler/src/adapter/BaseQuery.js	63.44% <0.00%> (-0.22%)	⬇️
...-query-orchestrator/src/orchestrator/QueryQueue.js	69.20% <0.00%> (-0.09%)	⬇️
packages/cubejs-api-gateway/src/gateway.ts	67.46% <0.00%> (ø)
packages/cubejs-schema-compiler/src/index.ts	100.00% <0.00%> (ø)
packages/cubejs-api-gateway/src/sql-server.ts	6.89% <0.00%> (ø)
... and 15 more

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